Process for selective preparation of secondary and tertiary amines

Abstract

Secondary and tertiary amines are selectively prepared by a process comprising reacting an olefin, a nitrogen-containing compound and synthesis gas in the presence of a catalyst system comprising a ruthenium-containing compound mixed with a quaternary onium salt, optionally in the presence of a solvent, heating the resultant mixture to a temperature of at least 100° C. and a pressure of at least 100 psi until there is substantial formation of the desired tertiary amine and separating the desired amine by a phase separation technique.

What is claimed is: 
     
       1. A process for preparing secondary and tertiary amines which comprises reacting an olefin, a nitrogen-containing compound from the group consisting of primary amines and secondary amines, carbon monoxide and hydrogen in the presence of a catalyst system consisting of a ruthenium-containing compound from the group consisting oxides of ruthenium, ruthenium salts of a mineral acid, ruthenium salts of an organic carboxylic acid, ruthenium complexes with carbonyl-containing ligands, ruthenium carbonyls and hydridocarbonyls and substituted species thereof mixed with a tetraalkylphosphonium salt, optionally in the presence of a solvent heating the resultant mixture to a temperature of between 100° C. and 300° C. and a pressure of between 400 and 4000 psi until there is substantial formation of the desired secondary or tertiary amines and separating the resulting product. 
     
     
       2. The process of claim 1 wherein the olefin is a straight-chain terminal olefin containing 2 to 25 carbon atoms. 
     
     
       3. The process of claim 1 wherein the olefin is a branched-chain terminal olefin. 
     
     
       4. The process of claim 1 wherein the olefin is an internal olefin. 
     
     
       5. The process of claim 1 wherein the nitrogen-containing compound is a secondary amine. 
     
     
       6. The process of claim 5 wherein the secondary amine is selected from the group consisting of pyrrolidine, diethylamine, dimethylamine, morpholine and di-n-propylamine. 
     
     
       7. The process of claim 1 wherein the primary amine is selected from the group consisting of methylamine, ethylamine, n-hexylamine, and tert-butylamine. 
     
     
       8. The process of claim 1 wherein the process is conducted with a ratio of CO to H 2  of about 1:5 to 5:1. 
     
     
       9. The process of claim 1 wherein the ruthenium-containing compound is selected from the group consisting of ruthenium dioxide hydrate, ruthenium tetraoxide, anhydrous ruthenium(IV) oxide, ruthenium acetate, ruthenium(III) acetylacetonate and triruthenium dodecacarbonyl. 
     
     
       10. The process of claim 9 wherein the ruthenium-containing compound is selected from the group consisting of ruthenium(IV) oxide and triruthenium dodecacarbonyl. 
     
     
       11. The process of claim 2 wherein the straight-chain terminal olefin is selected from the group consisting of 1-octene, 1-decene, 1-dodecene, and propylene. 
     
     
       12. The process of claim 3 wherein the branched-chained terminal olefin is 3,3-dimethyl-1-butene. 
     
     
       13. The process of claim 1 wherein the tetraalkylphosphonium salt is selected from the group consisting of tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium iodide, tetrabutylphosphonium acetate and tetrabutylphosphonium chromate. 
     
     
       14. The process of claim 13 wherein the tetrabutylphosphonium salt is tetrabutylphosphonium bromide. 
     
     
       15. The process of claim 1 wherein a solvent is used which comprises an aromatic or aliphatic amide solvent. 
     
     
       16. The process of claim 15 wherein the amide solvent is selected from the group consisting of N-isopropylpyrrolidone, N-hydroxyethylpyrrolidone, N-methyl pyrrolidone and N,N-dimethylformamide. 
     
     
       17. The process of claim 16 wherein the amide solvent is N,N-dimethylformamide. 
     
     
       18. The process of claim 1 wherein an aromatic or aliphatic ether solvent is used. 
     
     
       19. The process of claim 18 wherein the ether solvent is selected from the group consisting of p-dioxane, tetrahydrofuran and diethyl ether. 
     
     
       20. The process of claim 1 wherein an aromatic hydrocarbon solvent is used. 
     
     
       21. The process of claim 20 wherein the aromatic hydrocarbon solvent is toluene. 
     
     
       22. The process of claim 1 wherein the preferred temperature range is from 120° C. to 220° C. 
     
     
       23. The process of claim 1 wherein the pressure is from 500 psi to 2000 psi. 
     
     
       24. A process for preparing secondary and tertiary amines comprising reacting an olefin, a nitrogen-containing compound, carbon monoxide and hydrogen in the presence of a catalyst system comprising a ruthenium compound, a quaternary phosphonium salt and an amide solvent, heating the resultant mixture to a temperature of at least 120° C. and a pressure of at least 500 psi until there is substantial formation of the desired tertiary amine product, allowing then the separation of the reaction mixture into two distinct phases consisting of an upper phase containing the product amine and a lower phase containing the reusable catalyst, by-products and other substances, removing the upper phase, and recovering the desired secondary or tertiary amine product.